Fix an overflow in valueAsDate setter of temporal input types.

third_party/WebKit/Source/wtf/DateMath.cpp

 /*
  * Copyright (C) 1999-2000 Harri Porten (porten@kde.org)
  * Copyright (C) 2006, 2007 Apple Inc. All rights reserved.
  * Copyright (C) 2009 Google Inc. All rights reserved.
  * Copyright (C) 2007-2009 Torch Mobile, Inc.
  * Copyright (C) 2010 &yet, LLC. (nate@andyet.net)
  *
  * The Original Code is Mozilla Communicator client code, released
  * March 31, 1998.
  *
@@ skipping 81 matching lines @@
 #endif
 
 namespace WTF {
 
 /* Constants */
 
 static const double hoursPerDay = 24.0;
 static const double secondsPerDay = 24.0 * 60.0 * 60.0;
 
 static const double maxUnixTime = 2145859200.0; // 12/31/2037
+static const double kMinimumECMADateInMs = -8640000000000000.0;
+static const double kMaximumECMADateInMs = 8640000000000000.0;
 
 // Day of year for the first day of each month, where index 0 is January, and day 0 is January 1.
 // First for non-leap years, then for leap years.
 static const int firstDayOfMonth[2][12] = {
     {0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334},
     {0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335}
 };
 
 static inline void getLocalTime(const time_t* localTime, struct tm* localTM)
 {
@@ skipping 47 matching lines @@
 static void appendTwoDigitNumber(StringBuilder& builder, int number)
 {
     ASSERT(number >= 0 && number < 100);
     if (number <= 9)
         builder.append('0');
     builder.appendNumber(number);
 }
 
 int msToYear(double ms)
 {
+    DCHECK(std::isfinite(ms));
+    DCHECK_GE(ms, kMinimumECMADateInMs);
+    DCHECK_LE(ms, kMaximumECMADateInMs);
     int approxYear = static_cast<int>(floor(ms / (msPerDay * 365.2425)) + 1970);
     double msFromApproxYearTo1970 = msPerDay * daysFrom1970ToYear(approxYear);
     if (msFromApproxYearTo1970 > ms)
         return approxYear - 1;
     if (msFromApproxYearTo1970 + msPerDay * daysInYear(approxYear) <= ms)
         return approxYear + 1;
     return approxYear;
 }
 
 int dayInYear(double ms, int year)
@@ skipping 645 matching lines @@
 }
 
 double convertToLocalTime(double ms)
 {
     double utcOffset = calculateUTCOffset();
     double dstOffset = calculateDSTOffset(ms, utcOffset);
     return (ms + utcOffset + dstOffset);
 }
 
 } // namespace WTF